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The Xpert HCV test, performed on the GeneXpert Xpress System, is an automated in vitro reverse transcription polymerase chain reaction (RT-PCR) test for the qualitative detection of hepatitis C virus (HCV) RNA in human fingerstick K2-EDTA whole blood from adult individuals at risk and/or with signs and symptoms of HCV infection with or without antibody evidence of HCV infection. Detection of HCV RNA indicates that the virus is replicating and therefore is evidence of active infection. Detection of HCV RNA does not discriminate between acute and chronic states of infection. The Xpert HCV test is not intended for monitoring patients undergoing treatment or for use in screening blood, plasma, or tissue donors.

The Xpert HCV test, is an automated qualitative in vitro reverse transcription polymerase chain reaction (RT-PCR) test. The Xpert HCV test is performed on the GeneXpert Xpress System. With this system an operator can run the test by performing four steps: 1) mix the specimen. 2) transfer the liquid sample to the cartridge with a transfer pipette, 3) run the test on the instrument, and 4) read the results. The GeneXpert Xpress System (Hub configuration) consists of a GeneXpert IV instrument that conducts the sample preparation, nucleic acid amplification and real-time fluorescent signal detection for the test, and a GeneXpert Hub with preloaded GeneXpert Xpress software for running the tests and viewing the results. The GeneXpert Hub accessory integrates the computer, touchscreen monitor and barcode scanner. Each of the GeneXpert modules in the GeneXpert IV instrument can perform separate sample preparation and testing. The module contains a syringe drive for dispensing fluids (i.e., the syringe drive activates the plunger that works in concert with the rotary valve in the cartridge to move fluids between chambers), an ultrasonic horn for lysing cells or spores, and a proprietary I-CORE (Intelligent Cooling/Heating Optical Reaction) thermocycler for performing real-time PCR and RT-PCR and detection. The Xpert HCV test requires the use of a single-use disposable GeneXpert cartridge that contains all necessary reagents for the detection of HCV RNA. Because the cartridges are self-contained, the risk of cross-contamination between samples is minimized. The Xpert HCV test includes reagents for the detection of HCV RNA in clinical specimens as well as a sample processing control (SPC) and internal control high (IC-H) used to control for adequate processing of the target and to monitor the presence of inhibitor(s) in the RT and PCR reactions. The Probe Check Control (PCC) verifies reagent rehydration. PCR tube filling in the cartridge, probe integrity, and dye stability. The Sample Volume Adequacy (SVA) control ensures the sample was correctly added to the cartridge and verifies that the correct volume of sample has been added to the sample chamber. The Xpert HCV test is designed for use with human K2-fingerstick EDTA whole blood. The BD Microtainer for capillary whole blood collection was validated for use with the Xpert HCV test. After collecting human fingerstick EDTA whole blood in the BD Microtainer, a 100μl aliquot of the specimen is transferred to the sample chamber of the Xpert HCV cartridge using the transfer pipette supplied in the Xpert HCV kit. The sample results are interpreted by the GeneXpert Xpress System from measured fluorescent signals and embedded calculation algorithms and are shown in the View Results window. It also reports if the test has encountered an instrument error or produces no result and needs to be repeated.